INDUCTION OF DIFFERENTIATION OF EMBRYONAL CARCINOMA F9 CELLS BY IRON CHELATORS

The effects of several chelators, including hinokitiol, on embryonal c arcinoma F9 cell differentiation were assessed by assaying the product ion of plasminogen activator (PA) as a differentiation marker protein. Hinokitiol and tropolone which were potent differentiation inducers l ost their activity following preincubation with Fe2+ and Fe3+ ions. Ot her metal ions had no or little effect on the hinokitiol-induced diffe rentiation. Of several chelators examined, dithizone induced different iation as effectively as did hinokitiol and tropolone. Dithizone-induc ed differentiation was also inhibited by preincubation with Fe3+ ions. It was concluded that some potent iron chelators could trigger the te ratocarcinoma F9 cells to differentiate through the chelation with int racellular iron ions.